Before buying the application, there is a piece of information for digestion.
I bought the app on the 13rd of October. I'm not native English speaker. However, my English level is Upper-Intermediate. I carry on learning English and practising my reading ability on the application.
As it has turned out, my average reading speed is 65 WpM. It has lasted 15 days since I started doing those exercises. I should read and look for answers as fast as I can. The ability is crucially needed for IELTS preparations and exam. Basically, I had asked myself - why not?
If truth to be told, the software company alleges that some users have succeeded in improving reading speed double, furthermore, other users managed to boost reading speed triple.
Overall, I have spent more than 16 hours for the last two week. You can have a look at the statistic. I cannot find 20-40% of my improvement. I really suppose that all these claims are for increasing profit of the company. It is an urban myth which has no foundation. In other other words it is marketing only.
What kind of minuses I have found:
1) The language is used American English. I always thought that authentic English is British. If the application takes spellings into account (e.g. colour and color or rumor and rumour) please, I would like to get a British English version.
2) The application has some obvious faults of developers. Before you start doing an exercise you are given a window of a description. Try turning the volume up/down or if you have a stylus, try clicking on "start". The window will be closed.
3) When you do some exercise the application rotates screen through 90 degrees without any reason (Galaxy Note II).
4) The speed of WpM differs dramatically between two types of exercises. The first one is supposed to improve retention. The second one is practical. The difference between both of them is 120-180WpM and 240-350WpM respectively.
5) "Text search" is completely wrong. I can see the index which has an extraordinary turbulence in the graph like, 35-100-35-90. It means that the algorithm has not been pondered. The size of texts changes alike.
I would write about the application more, unfortunately, I lack of time. I set the worst mark on Google Play! Anyway, I am going to keep practising assiduously for a few months, I would change my mind as soon as I notice some improvement.